RU2658274C2 - Fabric and molded article formed by molding the same - Google Patents

Abstract

FIELD: weaving.

SUBSTANCE: in the fabric, one kind of the warp and the weft is a polyamide resin fiber comprising a polyamide resin composition, and the other is a continuous carbon fiber. Average fiber length of the continuous carbon fiber in a discretionary square portion of the fabric in which one side of the square is parallel to the warp and another side of the square is parallel to the weft is 1.1-1.6 times the length of one of the sides of the square. Polyamide resin composition comprises a polyamide resin in which 50 mol% or more of a diamine constituent unit is derived from a xylylenediamine, number-average molecular weight (Mn) is 6,000-30,000, and the molecular weight of 0.5-5 mass% thereof is 1,000 or less.

EFFECT: provided is a fabric that exhibits excellent mechanical strength and shaping properties.

9 cl, 1 dwg

Description

FIELD OF THE INVENTION

The present invention provides a fibrous web using specific polyamide polymer fibers and continuous carbon fibers. The present invention also provides a molded article obtained by molding such a fibrous web.

State of the art

A fiber reinforced and polymer-based composite material made by combining a fibrous material and a matrix polymer has the advantages of low density and high stiffness, so that a molded article containing this fiber-reinforced and polymer-based composite material is widely used to to produce mechanical parts, parts for electrical / electronic equipment, parts / elements of vehicles, parts for aircraft / aer space equipment, etc. The fibrous material used is typically carbon fiber.

On the other hand, the matrix polymer, which is commonly used in this way, is a thermosetting polymer such as an unsaturated polyester polymer and an epoxy polymer, taking into account mechanical strength, affinity for the fibrous material, formability, etc. A molded product that uses thermosetting polymer has such a major drawback that it cannot be re-melted for molding.

In such a situation, the applicant of the present invention described in Patent Document 1 a composite material having a polyamide polymer base obtained by impregnating a fibrous material with a polyamide polymer, wherein the polyamide polymer is characterized in that 50 mol.% Or more of the diamine structural units forms xylylenediamine, so that the number average molecular weight ( Mn) of the polyamide polymer is from 6000 to 30000, and that the content of components in which the molecular weight is 1000 or less is from 0.5 to 5 wt. %

Bibliography

Patent documents

Patent Document 1: Japanese Patent No. 4894982

SUMMARY OF THE INVENTION

Technical problem

Although the composite material having a polyamide polymer base described in Patent Document 1 is a material having high moldability, an even higher moldability is required for the manufacture of molded articles having more complex three-dimensional shapes. Of course, the mechanical strength of a heat-treated composite material having a polyamide polymer base is also required. In addition, the molded product must also have a good appearance, even after processing when heated. Thus, it is an object of the present invention to provide a polyamide-based polymer composite material exhibiting excellent mechanical strength and good appearance even after processing by heating.

Solution

As a result of comprehensive studies conducted in such circumstances, the authors of the present invention found that the fibrous web in which the yarns of one kind (warp or weft) is a polyamide polymer fiber containing a particular polyamide polymer composition and the yarns of another of the kind constitutes a continuous carbon fiber, so that a predetermined level of flexibility is provided. The discovery of this fact led the authors to carry out the present invention. More specifically, the problems described above are solved by paragraph 1 below, and more preferably by paragraphs 2-6 above.

1. A fibrous web including warp and weft yarns, in which yarns of one kind from warp and weft yarns comprise a polyamide polymer fiber containing a polyamide polymer composition, and yarns of another kind comprise continuous carbon fiber; in an arbitrary square region of the fibrous web, one side of an arbitrary square region is oriented parallel to the warp threads, and the other side of an arbitrary square region is parallel to the weft threads, the continuous carbon fiber has an average length of 1.1-fold to 1.6- multiple lengths of the side of the square; the polyamide polymer composition comprises a polyamide polymer in which 50 mol% or more of diamine structural units forms xylylenediamine; and in which the polyamide polymer has a number average molecular weight (Mn) of from 6,000 to 30,000, and from 0.5 to 5 wt. % of the polyamide polymer has a molecular weight of 1000 or less.

2. The fibrous web according to claim 1, wherein the polyamide polymer fiber has an average length from 1.0 times to 1.6 times the length of the side of the square.

3. The fibrous web according to paragraph 1 or 2, having a surface density of from 50 to 1000 g / m ² .

4. The fibrous web according to any one of paragraphs 1-3, in which the polyamide polymer contains 0.01 to 1 wt. % cyclic compound.

5. The fibrous web according to any one of paragraphs 1-4, having a ratio of the average linear density of the polyamide polymer fiber and the average linear density of a continuous carbon fiber (average linear density of a polyamide polymer fiber / average linear density of a continuous carbon fiber) from 20/80 to 80/20 .

6. A molded product obtained by molding a fibrous web according to any one of paragraphs 1-5.

Beneficial effects of the invention

By means of the present invention, it is now possible to produce a composite having a polyamide polymer base that exhibits good molding suitability, high mechanical strength and good appearance after processing by heating.

Brief Description of the Drawings

[FIG. 1] FIG. 1 is a schematic diagram illustrating an exemplary square sample (X) of a fibrous web according to the present invention.

Description of Embodiments

The present invention will be described in detail below. As mentioned herein, each numerical range expressed by two values in the form of “from ... to” is an interval including values indicated as its lower and upper limits.

Linear density according to the present invention means the average linear density, measured at 10 randomly selected points of the fiber, unless otherwise determined by a specific condition.

The term “parallel” according to the present invention means not only perfect parallelism, but also approximate parallelism. For example, in the present description, the warp yarns in the regularly structured region of the fibrous web are parallel to each other, and the weft yarns in the same region are also parallel to each other.

The fibrous web according to the present invention is characterized in that the fibrous web includes warp and weft yarns, wherein the yarns of one kind of warp and weft yarns comprise a polyamide polymer fiber in which the polyamide polymer composition is contained and the yarns of another kind comprise continuous carbon fiber; in an arbitrary square region of the fibrous web (sometimes hereinafter referred to as “square (X)”), one side of an arbitrary square region is oriented parallel to the warp threads, and the other side of an arbitrary square region is oriented parallel to the weft threads, continuous carbon the fiber has an average length of 1.1 to 1.6 times the length of the side of the square; the polyamide polymer composition comprises a polyamide polymer in which 50 mol% or more of diamine structural units forms xylylenediamine; and in which the polyamide polymer has a number average molecular weight (Mn) of from 6,000 to 30,000, and from 0.5 to 5 wt. % of the polyamide polymer has a molecular weight of 1000 or less.

With this configuration, the fibrous web is now able to strike a balance between formability and mechanical strength, which are generally considered to be contradictory.

The fibrous web according to the present invention is generally such that the yarns of one kind of warp and weft yarns comprise a polyamide polymer fiber in which the polyamide polymer composition is contained, and the yarns of another kind comprise a continuous carbon fiber. Polyamide polymer fibers and the continuous carbon fibers that make up the warp and weft threads typically form a bundle of polyamide polymer fibers and a bundle of continuous carbon fibers. Each of these fiber bundles, which are used here, can be produced, as a rule, by treating the fibers with a processing substance to convert the fibers into bundles. These fibers will be described in detail below.

According to the present invention, in square (X), the continuous carbon fiber has an average length that is from 1.1 times to 1.6 times, and preferably from 1.2 times to 1.5 times the length of the side of the square. At these intervals, the advantages of the present invention are generally more effective.

According to the present invention, also in square (X), the polyamide polymer fiber has an average length of preferably from 1.0 times to 1.6 times the length of the side of the square (X), and this ratio is preferably from 1.1 to 1 , 5 and, in particular, from 1.1 to 1.2. At these intervals, the advantages of the present invention are generally more effective.

A square (X) in this context means a square region selected from a regularly structured region of the fibrous web, with one side of the square oriented parallel to the warp threads and the other side of the square oriented parallel to the weft threads. FIG. 1 illustrates an exemplary square (X) of a fibrous web according to the present invention, wherein in this square, the vertical lines are warp threads and the horizontal lines are weft threads. Accordingly, any arbitrary square of the fibrous web has equal average lengths.

As the shape of the fibrous web according to the present invention, a smooth woven web, an eight-knit satin web, a four-knit satin web, twill, etc. is arbitrarily selected. without particular limitation, with a smooth woven fabric is preferred. A smooth woven fabric may also be a so-called matting weave. The fibrous web is preferably a smooth woven web and more preferably a smooth woven web made in such a way that each individual warp yarn and each individual weft yarn intersect, passing alternately from above and then from below with respect to each other. A fibrous web can be made by any of the well-known methods.

The fibrous web according to the present invention preferably has a surface density of 50 to 1000 g / m ² and more preferably 100 to 900 g / m ² . At these intervals, the suitability for processing the fibrous web is improved, the fibrous web is less likely to cause a fiber shift in the subsequent process of forming the fibrous web, and as a result, a molded article having improved mechanical strength is obtained.

Next, a polyamide polymer fiber and a continuous carbon fiber that are used according to the present invention will be described.

Polyamide Polymer Fiber

The polyamide polymer fiber used according to the present invention is a fibrous product from a polyamide polymer composition that contains a polyamide polymer in which 50 mol% or more of diamine structural units forms xylylenediamine, the polyamide polymer has a number average molecular weight (Mn) of 6000 to 30000, and from 0.5 to 5 wt. % of the polyamide polymer has a molecular weight of 1000 or less.

The polyamide polymer fibers that is used according to the present invention are preferably a bundle of polyamide polymer fibers in which the surface of the fibers is treated with a treatment substance.

Characteristics of Polyamide Polymer Fiber

The polyamide polymer fiber that is used according to the present invention is a continuous fiber product of a polyamide polymer composition and has a length exceeding 6 mm. Although the average length of the polyamide polymer fiber used according to the present invention is not particularly limited, it is preferably in the range of 1 to 20,000 m, more preferably 100 to 10,000 m, and even more preferably 1,000 to 7,000 m, taking into account the improvement in suitability for molding.

The polyamide polymer fiber that is used according to the present invention is typically made using a bundle of polyamide polymer fibers, which is a bundle of polyamide polymer fibers, in which the total linear density per one bundle of polyamide polymer fibers is preferably from 40 to 600 dtex, more preferably 50 to 500 dtex; and even more preferably 200 to 400 dtex. At these intervals, the advantages of the present invention will be manifested more effectively. The number of fibers that form the bundle of polyamide polymer fibers is preferably from 1 to 200 fibers, more preferably from 1 to 50 fibers, even more preferably from 5 to 45 fibers and, in particular, from 20 to 40 fibers. At these intervals, the advantages of the present invention will be manifested more effectively.

The bundle of polyamide polymer fibers used according to the present invention preferably has a tensile strength of 2 to 10 gf / d. In this range, the advantages of the present invention are generally more effective.

Substances for processing polyamide polymer fiber

The polyamide polymer fiber that is used according to the present invention is preferably used in the form of a fiber bundle after treatment with a treatment substance.

A substance for processing a polyamide polymer fiber, which is used according to the present invention, is not limited in a certain way, and is considered sufficient if the substance for processing by its action combines polyamide polymer fibers into a fiber bundle. Preferred exemplary processing agents are ester-based compounds, alkylene glycol-based compounds, polyolefin-based compounds and phenyl ether-based compounds, with more preferred examples being surfactants.

In the case of its use, the expendable amount of the substance for processing polyamide polymer fibers is preferably from 0.1 to 2% and more preferably from 0.5 to 1.5% with respect to the weight of the polyamide polymer fibers.

A method of treating a polyamide polymer fiber with a treatment substance

A method for treating a polyamide polymer fiber with a treatment substance is not limited in a specific way, provided that the expected goal is achieved. An exemplary method is the addition of polyamide polymer fibers to a solution containing a solute for processing, whereby the treatment substance is able to adhere to the surface of the polyamide polymer fibers. Alternatively, the treatment can be carried out by blowing air.

Polyamide Polymer Composition

The polyamide polymer fiber according to the present invention constitutes a polyamide polymer composition, the polyamide polymer composition being mainly a polyamide polymer (polyamide polymer is typically 90% or more based on the weight of the composition). The polyamide polymer is such that 50 mol% or more of the diamine structural units of the polyamide polymer forms xylylenediamine, that the polyamide polymer has a number average molecular weight (Mn) of from 6,000 to 30,000, and from 0.5 to 5 wt. % of the polyamide polymer has a molecular weight of 1000 or less.

The polyamide polymer used according to the present invention is a fibrous product consisting of a polyamide polymer in which 50 mol% or more of the diamine structural units of the polyamide polymer (the structural unit that forms the diamine) forms xylylenediamine. Thus, the polyamide polymer is a xylylenediamine-based polyamide polymer in which 50 mol% or more of the diamine structural units forms xylylenediamine, and which is a polycondensation product of the diamine with dicarboxylic acid. The polyamide polymer is a polyamide polymer having a xylylenediamine base in which 70 mol% or more, and preferably 80 mol% or more, of the diamine structural units is formed by m-xylylenediamine and / or p-xylylenediamine, and preferably 50 mol% or more more preferably 70 mol.% or more and, in particular, 80 mol.% or more of the structural units of the dicarboxylic acid (the structural unit that the dicarboxylic acid forms) forms an unbranched chain α, ω-aliphatic dicarboxylic acid containing from 4 to 20 at mov carbon.

Exemplary diamines that are not m-xylylenediamine and p-xylylenediamine and are suitable for use as the starting diamine component for the xylylene diamine-based polyamide polymer are aliphatic diamines such as tetramethylene diamine, pentamethylene diamine, 2-methylpentanediamine diamine, octamethylene diamine, nonamethylene diamine, decamethylene diamine, dodecamethylene diamine, 2,2,4-trimethylhexamethylenediamine and 2,4,4-trimethylhexamethylenediamine; alicyclic diamines such as 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, bis (4-aminocyclohexyl) methane, 2,2-bis (4-aminocyclohexyl) propane, bis (aminomethyl) decalin and bis (aminomethyl) tricyclodecane; and aromatic diamines such as bis-4-aminophenyl ether, paraphenylenediamine, and bis (aminomethyl) naphthalene, all of which can be used independently, or two or more compounds can be used in combination.

When a diamine, which is not xylylenediamine, is used as the diamine component, the corresponding ratio in use is preferably 50 mol% or less, more preferably 30 mol% or less, even more preferably 1 to 25 mol%, and in particular from 5 to 20 mol.% diamine structural units.

Exemplary straight chain, α, ω-aliphatic dicarboxylic acids containing from 4 to 20 carbon atoms, which can preferably be used as the starting component of the dicarboxylic acid for the polyamide polymer, are aliphatic dicarboxylic acids such as succinic acid, glutaric acid, pimelic acid , suberic acid, azelaic acid, adipic acid, sebacic acid, undecandicarboxylic acid, and dodecandicarboxylic acid, all of which can be used independently, or two or more compounds may be used in combination. Among them, adipic acid and sebacic acid are preferred since the resulting polyamide polymer will have a melting point suitable for molding. Sebacic acid is particularly preferred.

Exemplary dicarboxylic acid components that are not straight chain α, ω-aliphatic dicarboxylic acids having from 4 to 20 carbon atoms are phthalic acid type compounds such as isophthalic acid, terephthalic acid and orthophthalic acid; and naphthalenedicarboxylic acids, including the following isomers: 1,2-naphthalenedicarboxylic acid, 1,3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 1,7-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid and 2,7-naphthalenedicarboxylic acid, all of which can be used independently, or two or more compounds can be used in combination.

When a dicarboxylic acid, which is not a straight chain α, ω-aliphatic dicarboxylic acid containing from 4 to 20 carbon atoms, is used as a component of a dicarboxylic acid, it is preferable to use terephthalic acid or isophthalic acid in terms of formability and protective properties . The ratio of terephthalic acid to isophthalic acid is preferably 30 mol% or less, more preferably 1 to 30 mol% and, in particular, 5 to 20 mol% of the structural units of the dicarboxylic acid.

As a constituent component of the polyamide polymer, which is not a diamine component and a dicarboxylic acid component, lactams such as ε-caprolactam and laurolactam, as well as aliphatic aminocarboxylic acids such as aminocaproic acid and aminoundecanoic acid are also suitable for use as a copolymerizable component. which do not impair the advantages of the present invention.

Preferred examples of the polyamide polymer include a poly-m-xylylene adipamide polymer, a poly-m-xylylene-sebacemide polymer, a poly-p-xylylene-sebaceamide polymer and a mixed poly-m-xylylene / p-xylylene adipamide polymer obtained by polycondensation of a mixture of xylidene xylylenediamine, with adipic acid. Relevant more preferred examples include a poly-m-xylylene-sebaceamide polymer, a poly-p-xylylene-sebaceamide polymer and a mixed poly-m-xylylene / p-xylylene-sebaceamide polymer obtained by polycondensation of a mixture of xylylenediamine and p-cis-acid diamine. These polyamide polymers typically have improved moldability.

According to the present invention, the polyamide polymer has a number average molecular weight (Mn) of from 6,000 to 30,000, and from 0.5 to 5 wt. % of the polyamide polymer has a molecular weight of 1000 or less.

If the number average molecular weight (Mn) is outside the range of 6,000 to 30,000, the resulting fibrous web or molded article will have reduced strength. The number average molecular weight (Mn) is preferably in the range of 8000 to 28000, more preferably is in the range of 9000 to 26000, even more preferably is in the range of 10,000 to 24,000, in particular 11,000 to 22,000, and in particular 12,000 to 20,000 In these intervals, thermal stability, elastic modulus, dimensional stability and moldability are provided at good levels.

Further, in this context, the number average molecular weight (Mn) is calculated using the equation below, where the concentration of terminal amino groups [NH ₂ ] (meq / g) and the concentration of terminal carboxyl groups [COOH] (meq / g) of the polyamide polymer are used.

Number average molecular weight (Mn) = 2,000,000 / ([COOH] + [NH ₂ ])

Polyamide polymer necessarily contains from 0.5 to 5 wt. % polyamide polymer in which the molecular weight is 1000 or less. Due to the content of such an amount of such a low molecular weight component, the polyamide polymer acquires improved impregnation characteristics or improved fluidity through the reinforcing fibers in the polyamide polymer during processing during heating, so that pores can be prevented during processing, and the resulting molded article can acquire increased strength. If its content exceeds 5 wt. %, the low molecular weight component will spread, reducing strength and impairing the appearance of the molded product.

The content of the component in which the molecular weight is 1000 or less, is preferably from 0.6 to 4.5 wt. %, preferably from 0.7 to 4 wt. %, even more preferably from 0.8 to 3.5 wt. %, in particular, from 0.9 to 3 wt. % and most preferably from 1 to 2.5 wt. %

The content of the low molecular weight component in which the molecular weight is 1000 or less is controlled by changing the melt polymerization condition, including the temperature and polymerization pressure of the polyamide polymer, as well as the rate of dropwise addition of diamine. The content of the low molecular weight component is controlled in an arbitrary ratio, in particular by reducing the pressure inside the reactor at the final stage of polymerization in the melt, and as a result, the low molecular weight component is removed. Alternatively, the polyamide polymer made by melt polymerization can be extracted with hot water to remove the low molecular weight component, or after the polymerization in the melt, solid phase polymerization under reduced pressure can be performed to remove the low molecular weight component. In solid phase polymerization, the content of the low molecular weight component is controlled at an arbitrary level by changing the temperature or degree of vacuum. As a further alternative, the content of the low molecular weight component in which the molecular weight is 1000 or less is controlled by its subsequent addition to the polyamide polymer.

Further, the content of a component with a molecular weight of 1000 or less can be measured by gel permeation chromatography (GPC) using an HLC-8320GPC instrument from Tosoh Corporation, and expressed as equivalent values relative to the standard of polymethyl methacrylate (PMMA). The measurement can be carried out using two columns of TSK gel Super HM-H, a solution of 10 mmol / L sodium trifluoroacetate in hexafluoroisopropanol (HFIP) as a solvent at a polymer concentration of 0.02 wt. %, column temperature 40 ° C, flow rate 0.3 ml / min and a refractive index detector (RI). A calibration curve is constructed using solutions having 6 levels of PMMA concentration in HFIP.

In the polyamide polymer composition, it is preferable that from 0.01 to 1 wt. % of the polyamide polymer is a cyclic compound (polyamide polymer). A cyclic compound according to the present invention means a ring-shaped salt consisting of a diamine component and a dicarboxylic acid component, which are the starting materials for the polyamide polymer, and can be quantified using the method described below.

The granule of the polyamide polymer is crushed using an ultracentrifugal mill, sieved through a sieve with a mesh size of 0.25 mm, and a 10 g sample of the resulting powder sample having a particle size of 0.25 mm or less is placed in a filter paper sleeve. The sample was then extracted using 120 ml of methanol for 9 hours using a Soxhlet extractor, and the resulting liquid extract was evaporated to a volume of 10 ml in an evaporator, taking measures to prevent the extract from evaporating to dryness. Any oligomer that may precipitate in this process is appropriately removed by filtration through a PTFE filter. The resulting liquid extract was diluted 50 times with methanol and quantified by high performance liquid chromatography (HPLC) using an appropriate device from Hitachi High-Technologies Corporation to determine the cyclic compound content.

When the cyclic compound is contained in such an interval, the resulting fibrous web and the molded product using it can acquire increased strength, reduced tendency to warp, and, as a rule, additionally improved dimensional stability.

The content of the cyclic compound is preferably from 0.05 to 0.8% and more preferably from 0.1 to 0.5% with respect to the weight of the polyamide polymer.

In many cases, a polyamide polymer made by melt polymerization contains a significant amount of a cyclic compound, which is typically removed by extraction with hot water. The amount of cyclic compound can be controlled by varying the degree of extraction with hot water. Alternatively, control can be carried out by changing the pressure during melt polymerization.

The polyamide polymer used according to the present invention preferably has a molecular weight distribution or a ratio of weight average molecular weight to number average molecular weight (Mw / Mn) of 1.8 to 3.1. The molecular weight distribution is preferably from 1.9 to 3.0, and even more preferably from 2.0 to 2.9. When the molecular weight distribution is in these ranges, it becomes even simpler to obtain a fibrous web having good mechanical characteristics.

The molecular weight distribution of the polyamide polymer can be controlled by appropriately selecting the type and amount of initiator or catalyst used for the polymerization, as well as the conditions for the polymerization reaction, such as temperature, pressure, reaction time, etc. The molecular weight distribution can also be controlled by mixing many types of polyamide polymers having different average molecular weights and obtained under different polymerization conditions, or by subjecting the polyamide polymer to fractional precipitation after polymerization.

Molecular weight distribution can be determined by measurement by the GPC method. More specifically, the measurement is carried out using an HLC-8320GPC device from Tosoh Corporation, two TSK gel Super HM-H columns from Tosoh Corporation and a solution of 10 mmol / L sodium trifluoroacetate in hexafluoroisopropanol (HFIP) as eluent under the following conditions: polymer concentration 0.02 wt. %, column temperature 40 ° C, flow rate 0.3 ml / min and the use of a refractive index (RI) detector, and as a result, the molecular weight distribution is obtained as an equivalent value with respect to standard polymethyl methacrylate. A calibration curve is constructed using solutions having 6 levels of PMMA concentration in HFIP.

The polyamide polymer preferably has a viscosity of 50 to 1200 Pa · s, which is measured at a temperature exceeding 30 ° C. the melting point of the polyamide polymer, a shear rate of 122 s ⁻¹ and a moisture content of the polyamide polymer of 0.06 wt. % or less. If the melt viscosity is in this range, the polyamide polymer is more easily processed to produce a film or fiber. It should be noted that in those cases where the polyamide polymer has two or more melting points, as described below, the measurement is carried out by determining the melting temperature as the temperature at the top of the endothermic peak that is present on the high temperature side.

The melt viscosity is preferably in the range from 60 to 500 Pa · s and even more preferably from 70 to 100 Pa · s.

The melt viscosity of the polyamide polymer can be adjusted by appropriately selecting the ratio of the amount of the starting component of the dicarboxylic acid and the diamine component, the polymerization catalyst, the molecular weight modifier, the polymerization temperature and the polymerization duration.

The polyamide polymer preferably has a bending modulus after water absorption of 85% or more. When the conservation coefficient of the bending modulus after water absorption is in this range, the resulting fibrous web and the corresponding molded product, as a rule, are less affected by physical deterioration under conditions of high temperature and high humidity and are less susceptible to geometric changes, such as warping.

Here, the conservation coefficient of the bending modulus after water absorption is defined as the ratio (%) of the bending modulus of the test sample made of polyamide polymer after the absorption of 0.5 wt. % water and bending modulus after absorption of 0.1 wt. % water, and a higher ratio means that the bending modulus is less likely to decrease even after absorption of water.

The bending modulus conservation coefficient after water absorption is more preferably 90% or more, and even more preferably 95% or more.

The conservation coefficient of the bending modulus of the polyamide polymer after water absorption can be adjusted, as a rule, by changing the ratio when p-xylylenediamine and m-xylylenediamine are mixed, and the higher the relative content of p-xylylenediamine, the higher the bending modulus. It can also be adjusted by changing the degree of crystallinity of the sample under bending.

The degree of water absorption of the polyamide polymer, soaked in water at 23 ° C for one week, and then measured immediately after extraction from water and wiping, is preferably 1 wt. % or less, preferably 0.6 wt. % or less, and even more preferably 0.4 wt. % or less. In these intervals, the resulting fibrous web and the molded article composed of it are easier to protect from deformation due to water absorption, and foaming during molding of the fibrous web can be suppressed by heating and pressure, and as a result, a molded product having a lower bubble content can be obtained. .

The polyamide polymer used here has a terminal amino group ([NH ₂ ]) concentration of preferably less than 100 meq / g, more preferably 5 to 75 meq / g and even more preferably 10 to 60 meq / g, and it has a terminal concentration carboxyl groups ([COOH]), preferably less than 150 meq / g, more preferably 10 to 120 meq / g, and even more preferably 10 to 100 meq / g. When a polyamide polymer having such a terminal group concentration is used, the polyamide polymer tends to more readily stabilize the viscosity when a film or fiber is made from it, and generally reactivity to the carbodiimide compound is described, which is described later.

The ratio of the concentration of terminal amino groups to the concentration of terminal carboxyl groups ([NH ₂ ] / [COOH]) is preferably 0.7 or less, more preferably 0.6 or less, and in particular 0.5 or less.

If this ratio exceeds 0.7, it may become difficult to control the molecular weight of the polyamide during polymerization.

The concentration of terminal amino groups can be measured by dissolving 0.5 g of a polyamide polymer in 30 ml of a mixture of phenol and methanol (4: 1) as a solvent at a temperature of 20 ° C to 30 ° C during stirring and titration with a solution of 0.01 n hydrochloric acids. The concentration of terminal carboxyl groups can be measured by dissolving 0.1 g of a polyamide polymer in 30 ml of benzyl alcohol at 200 ° C and adding 0.1 ml of a phenol red solution at a temperature in the range from 160 ° C to 165 ° C. The resulting solution is titrated with a titrant, which is prepared by dissolving 0.132 g of KOH in 200 ml of benzyl alcohol (0.01 mol / l in terms of the concentration of KOH), and determine the end point where the transition of yellow to red becomes irreversible, and based on this, be calculated concentration.

The polyamide polymer according to the present invention has a molar ratio of reacted diamine units to reacted dicarboxylic acid units (number of moles of reacted diamine / number of moles of reacted dicarboxylic acid, sometimes referred to as the “reaction molar ratio”), preferably from 0.97 to 1.02. In such an interval, the regulation of the molecular weight and molecular weight distribution of the polyamide polymer in arbitrary intervals is simplified.

The reaction molar ratio is preferably less than 1.0, even more preferably less than 0.995 and, in particular, less than 0.990, with the lower limit being preferably 0.975 or more and more preferably 0.98 or more.

The reaction molar ratio (r) is determined using the equation below:

r = (1-cN-b (C-N)) / (1-cC + a (C-N)),

wherein:

a: M1 / 2

b: M2 / 2

c: 18.015 (molecular weight of water (g / mol))

M1: molecular weight of diamine (g / mol)

M2: molecular weight of dicarboxylic acid (g / mol)

N: terminal amino group concentration (eq / g)

C: concentration of terminal carboxyl groups (eq / g)

In the case where the diamine and dicarboxylic acid components each have different molecular weights are used as monomers for the synthesis of a polyamide polymer, of course, M1 and M2 are calculated depending on the mixing ratio (molar ratio) of the monomers mixed as starting materials . It should be noted that the molar ratio of the starting monomers corresponds to the reaction molar ratio if the synthesis tank is an ideal closed system. However, the actual synthesis device cannot be an ideal closed system, and thus the molar ratio of the starting materials does not always correspond to the reaction molar ratio. In addition, it is believed that the starting monomers do not always react completely, and thus that the molar ratio of the starting materials again does not always correspond to the reaction molar ratio. Accordingly, the reaction molar ratio means the molar ratio of actually reacted monomers, which is determined based on the concentration of the end groups of the resulting polyamide polymer.

The reaction molar ratio of the polyamide polymer can be adjusted by choosing appropriate parameters for the reaction conditions, which include the molar ratio of the starting component of the dicarboxylic acid and the starting diamine component, reaction time, reaction temperature, droplet rate of addition of xylylenediamine, pressure in the reaction time and pumping start time.

When the polyamide polymer is manufactured using the so-called salt method, the reaction molar ratio can be adjusted to 0.97 to 1.02, in particular, for example, by setting the ratio of the starting diamine component to the starting component of the dicarboxylic acid in this interval and ensuring that the reaction proceeds in sufficient degrees. In the case where the diamine is continuously added dropwise to the molten dicarboxylic acid, in addition to controlling the ratio of the starting reagents in this range, as an alternative, the level of reflux of the diamine can be controlled during the dropwise addition of diamine and the diamine added by drops to be removed from the reaction system. Diamine can be removed from the system, in particular by adjusting the temperature of the reflux condenser in the optimal range or by changing the shape and / or number of nozzles in the column containing nozzles, including the so-called Raschig rings, Lessing rings and saddle nozzles. Alternatively, the unreacted portion of the diamine can be removed, reducing the reaction time after dropwise addition. As a further alternative, the unreacted portion of the diamine can be removed from the system by optionally adjusting the rate of dropwise addition of diamine. Using these methods, it becomes possible to regulate the reaction molar ratio in a predetermined range, even if the ratio of the starting reagents is outside the target range.

A method of manufacturing a polyamide polymer is not limited to a specific way; on the contrary, it can be any of the well-known methods of polymerization under known conditions. During the polycondensation of the polyamide polymer, a small amount of monoamine or monocarboxylic acid can be added as a molecular weight modifier. For example, a polyamide polymer can be made by heating a salt comprising a diamine component containing xylylenediamine and a dicarboxylic acid, such as adipic acid or sebacic acid, in the presence of pressurized water, and performing the polymerization in the molten state while removing the added water or water released as a result of condensation. Alternatively, a polyamide polymer can be made by adding xylylenediamine directly to the molten dicarboxylic acid and performing polycondensation under normal pressure. In this case, so that the reaction system remains in the form of a homogeneous liquid, the diamine is gradually added to dicarboxylic acid, and polycondensation is carried out while heating the reaction system so that the reaction temperature does not fall below the melting point of the oligoamide and polyamide made from it.

The polyamide polymer, which is prepared by melt polymerization, can then be solid phase polymerized. The solid phase polymerization process is not limited to a specific way; on the contrary, it can be any of the well-known methods of polymerization under known conditions.

According to the present invention, the melting temperature of the polyamide polymer is preferably from 150 to 310 ° C, and more preferably from 180 to 300 ° C.

The glass transition temperature of the polyamide polymer is preferably from 50 to 100 ° C, more preferably from 55 to 100 ° C, and in particular from 60 to 100 ° C. At these intervals, the polyamide polymer typically has enhanced thermal stability.

Here, the melting temperature is the temperature at the apex of the endothermic peak observed by differential scanning calorimetry (DSC). The glass transition temperature is measured by first heating and melting the sample so as to eliminate any possible effects of thermal history on crystallinity, and then reheating the sample. Measurement can be carried out using, for example, a DSC-60 instrument from Shimadzu Corporation, approximately 5 mg of sample, nitrogen creating an atmosphere and entering at a flow rate of 30 ml / min, and heating at a rate of 10 ° C / min from room temperature to temperature , which is not less than the expected melting temperature, and the melting temperature is defined as the temperature at the top of the endothermic peak observed for the molten sample. The glass transition temperature is determined by rapidly cooling the molten polyamide polymer with solid carbon dioxide and then re-heating it at a rate of 10 ° C / min to a temperature of not less than the melting temperature.

The polyamide polymer composition used according to the present invention may comprise another polyamide polymer that is not the xylylenediamine-based polyamide polymer described above and the elastomeric component. Examples of another polyamide polymer are polyamide 66, polyamide 6, polyamide 46, polyamide 6/66, polyamide 10, polyamide 612, polyamide 11, polyamide 12, hexamethylene diamine, polyamide 66 / 6T, consisting of adipic acid and terephthalic acid, hexamethylene diamine and polyamide 6I / 6T, consisting of isophthalic acid and terephthalic acid. The amount of these compounds when mixed is preferably 5% or less and more preferably 1 wt. % or less with respect to the weight of the polyamide polymer composition.

Here, the elastomeric component suitable for use may be any of the well-known elastomers, including a polyolefin based elastomer, a diene based elastomer, a polystyrene based elastomer, a polyamide based elastomer, a polyester based elastomer, a polyurethane based elastomer, a fluorine-containing elastomer and an organosilicon-based elastomer, among which polyolefin-based elastomer and polystyrene-based elastomer are preferred.

In addition, a modified elastomer is preferably used as the elastomer, which is modified using the α, β-unsaturated carboxylic acid and the corresponding acid anhydride, or acrylamide and its derivative, in the presence or absence of a radical initiator, to obtain an elastomer compatible with the polyamide polymer.

The content of such another polyamide polymer or elastomer in the polyamide polymer composition is typically 30 wt. % or less, preferably 20 wt. % or less and, in particular, 10 wt. % or less.

For the polyamide polymer composition described above, individual compounds can be used independently, or multiple compounds in the form of a mixture can be used as polyamide polymers.

As a further alternative, individual compounds or a plurality of compounds can be added to the polyamide polymer composition used according to the present invention as polymers such as a polyester polymer, a polyolefin polymer, a polyphenylene sulfide polymer, a polycarbonate polymer, a simple polyphenylene ether polymer and a polystyrene polymer, without prejudice objectives and effects of the present invention. The amount of these polymers when mixed is preferably 10% or less, and more preferably 1% or less, based on the weight of the polyamide polymer composition.

Additives may also be added to the polyamide polymer composition used according to the present invention, which include stabilizers such as an antioxidant and a thermal stabilizer, a hydrolysis resistance modifier, a weathering stabilizer, a matting agent, an ultraviolet absorbing substance, a nucleating agent, a plasticizer , dispersing agent, flame retardant, antistatic agent, anti-staining agent, obstacle a gel forming agent, a coloring agent and a mold releasing agent, without prejudice to the objects and effects of the present invention. Details of these additives can be found in paragraphs 0130-0155 of Japanese Patent Specification No. 4894982, the contents of which are incorporated herein.

Continuous carbon fiber

The fibrous web of the present invention contains continuous carbon fiber. Continuous carbon fiber means carbon fiber having a length that exceeds 6 mm. Although the average length of the continuous carbon fiber bundles used according to the present invention is not particularly limited, it is preferably in the range from 1 to 10,000 m, more preferably from 100 to 10,000 m, and even more preferably from 1,000 to 7,000 in terms of improving molding suitability .

The continuous carbon fiber bundle has an average linear density of preferably 50 to 2000 tex (g / 1000 m), more preferably 60 to 800 tex and even more preferably 60 to 500 tex. In these intervals, machinability improves, and the resulting fibrous web has increased elastic modulus and strength values.

The continuous carbon fiber bundle preferably has an average tensile modulus of 50 to 1000 GPa. In this interval, the molded product will have additionally increased strength.

As the continuous carbon fiber, polyacrylonitrile-based carbon fiber and pitch-based carbon fiber are preferably used. In addition, carbon fibers produced from plants, such as lignin and cellulose, are suitable for use.

Continuous carbon fiber treatment agent

The continuous carbon fiber that is used according to the present invention is preferably treated with a treatment substance. Exemplary continuous carbon fiber processing agents are a surface treatment agent and an adhesive.

Exemplary surface treating agents are functional surface treating agents such as an epoxy-based compound, an acrylic-based compound, an isocyanate-based compound, a silane-based compound, and a titanate-based compound, which in particular are a binder on a silane-based titanate-based binder, etc., wherein a silane-based binder is preferred.

Exemplary silane-based binders are trialkoxylan or triaryloxy silane compounds such as aminopropyltriethoxysilane, phenylaminopropyltrimethoxysilane, glycidylpropyltriethoxysilane, methacryloxypropyltrimethoxysilane and vinyltriethoxysilane; ureidosilane, sulfidesilane, vinylsilane, and imidazolsilane.

Exemplary adhesives are preferably epoxy based polymers, such as an epoxy polymer such as bisphenol A; and ester-based vinyl polymers, examples of which are epoxy acrylate polymers containing an acrylic group or a methacrylic group in one molecule, such as vinyl ester polymers such as bisphenol A, vinyl ester polymers such as novolak and brominated vinyl ester polymers. In addition, urethane-modified polymers, which are epoxy-based polymers and vinyl ester-based polymers, are suitable for use.

The amount of treatment material is preferably from 0.001 to 1.5%, more preferably from 0.1 to 1.2%, and even more preferably from 0.5 to 1.1%, based on the weight of the continuous carbon fiber. At these intervals, the advantages of the present invention will be manifested more effectively.

Method for processing continuous carbon fiber with a treatment substance

A method for treating a continuous carbon fiber with a treatment material may be any of the known methods. For example, continuous carbon fiber is added to a solution that contains a treatment substance dissolved therein, so as to cause the treatment substance to adhere to the surface of the continuous carbon fiber. Alternatively, the treatment agent can be applied by blowing air onto the surface of a continuous carbon fiber.

A commercially available continuous carbon fiber that can be surface treated with a treatment agent, such as a surface treatment agent or an adhesive, can be used without modification. Alternatively, in order to treat a continuous carbon fiber with a desired amount of processing agent, the fiber can be washed first to remove the pre-applied surface treatment or adhesive, and then reprocessed.

Molded product

The fibrous web of the present invention can be molded using an extrusion die or similar device and molded to a shape that is suitable for use and then heated, or molded by heating.

The fibrous web of the present invention is suitable for use in a variety of molded articles. In particular, the fibrous web according to the present invention, which has good formability and mechanical strength, is preferably used for the manufacture of molded products, such as angled products, for example, housings for office equipment and communication equipment.

More specifically, the molded product according to the present invention is preferably used for the manufacture of parts and cases of electrical / electronic equipment such as personal computers, office equipment, audiovisual equipment and mobile phones, optical equipment, precision equipment, toys, household / industrial devices, as well as for manufacturing details of vehicles, aircraft and ships.

Example

The present invention will now be described in detail with examples. The materials, amount used, ratio, process parameters, procedures or processes can be modified accordingly without deviating from the idea of the present invention. Thus, the scope of the present invention is not limited to the specific examples that are described below.

1. The manufacture of polyamide polymer fiber

Polyamide polymer

As the polyamide polymer, a polyamide polymer obtained by the exemplary manufacturing method described below and a commercially available m-xylylene adipamide polymer (MXD6) described below was used.

MXD6 M-xylylene adipamide polymer: m-xylylene adipamide polymer (product S6007 from Mitsubishi Gas Chemical Company, Inc.), number average molecular weight 25,000, component content with a molecular weight of 1000 or less than 0.51 wt. %

An exemplary manufacturing method 1

Polyamide Synthesis (MPXD10)

Sebacic acid was heated and melted in a reaction tank under a nitrogen atmosphere, the contents were constantly stirred and heated to 235 ° C during the gradual dropwise addition of a mixture containing a 3: 7 molar ratio of p-xylylenediamine (from Mitsubishi Gas Chemical Company, Inc.) and m-xylylenediamine (from Mitsubishi Gas Chemical Company, Inc.), under pressure (0.35 MPa), so as to set the molar ratio of diamine to sebacic acid to about 1: 1. After completion of the dropwise addition, the reaction was continued for 60 minutes, and as a result, the content of the component in which the molecular weight was 1000 or less was regulated. After completion of the reaction, the contents were turned into fibers, granulated using a granulator, and polyamide (MPXD10) was obtained as a result. Hereinafter, this polyamide will be referred to as MPXD10.

An exemplary manufacturing method 2

Polyamide Synthesis (PXD10)

Accurate weights of 8950 g (44.25 mol) of sebacic acid (sebacic acid under the name TA from the company) were placed in a 50-liter reaction tank equipped with a stirrer, reflux condenser, refrigerator, thermometer, dropping funnel, nitrogen inlet tube and fiber extrusion head. Itoh Oil Chemicals Co., Ltd.), 12.54 g (0.074 mol) of calcium hypophosphite and 6.45 g (0.079 mol) of sodium acetate. After nitrogen was thoroughly forced out of the internal space of the reaction tank, the pressure was increased with nitrogen to 0.4 MPa, and sebacic acid melted uniformly with stirring during the temperature increase from 20 ° C to 190 ° C for 55 minutes. Then, 5960 g (43.76 mol) of p-xylylenediamine (from Mitsubishi Gas Chemical Company, Inc.) was added dropwise over 110 minutes with stirring. During this process, the temperature inside the reaction tank continuously increased to 293 ° C. During the dropwise addition, the pressure was set at 0.42 MPa, and the resulting water was removed from the system through a reflux condenser and a refrigerator. The temperature of the reflux condenser was regulated in the range from 145 to 147 ° C. After the gradual addition of p-xylylenediamine was completed, the polycondensation reaction continued for 20 minutes, while the pressure inside the reaction tank was 0.42 MPa. During this process, the temperature inside the reaction vessel increased to 296 ° C. After that, the pressure inside the reaction tank was reduced from 0.42 MPa to 0.12 MPa within 30 minutes. During this process, the temperature inside the reaction vessel increased to 298 ° C. Then, the internal pressure was reduced at a rate of 0.002 MPa / min to 0.08 MPa within 20 minutes, and as a result, the content of the component with a molecular weight of 1000 or less was regulated. The temperature inside the reaction tank after completion of the pressure reduction was 301 ° C. After that, the pressure in the system was increased using nitrogen, and the polymer was discharged through a fiber extrusion head to make fibers, while the temperature inside the reaction tank was maintained at 301 ° C, and the polymer having a temperature of 301 ° C was cooled in cooling water at 20 ° C and granulated to obtain approximately 13 kg of a polyamide polymer. The cooling time in cooling water was 5 seconds, and the fiber winding speed was 100 m / min. Hereinafter, this polyamide will be referred to as PXD10.

Methods for measuring the various physical properties of a polyamide polymer were the methods described in paragraphs 0157-0168 of Japanese patent No. 4894982.

The properties of the polyamide polymer are presented in the table below.

Table 1 Type of polyamide polymer MPXD10 PXD10 MXD6 [COOH] meq / g 110 205 60 [NH ₂ ] meq / g 40 17 twenty [NH ₂ ] / [COOH] - 0.36 0.08 0.33 Mn - 13333 9009 25,000 The content of the component in which the molecular weight is 1000 or less wt. % 0.75 1.33 0.51 Mw / mn - 2.00 2,55 1.86 Melt viscosity Pa⋅s 191 87 650 Bending modulus conservation coefficient % 93 one hundred 92

after water absorption Melting temperature ° C 215 280/290 239 Glass transition temperature ° C 63 75 85 Cyclic compound content wt. % 0.12 0.5 0.7 Degree of water absorption wt. % 0.42 0.49 0.54 Reaction molar ratio - 0.9894 0.9794 0,9951

Fabrication of Polyamide Polymer Fiber

Fiber was made from the polyamide polymer obtained in this way according to the procedures described below.

The polyamide polymer was dried using a vacuum dryer at 150 ° C for 7 hours, melted and extruded using a single screw extruder having a 30 mm diameter screw through an extrusion head having 60 holes to produce fibers. The extruded polymer was cooled to solidification by blowing air. The fiber was coated with the treatment substance using a roller, the lower part of which was in the treatment substance, passed through a plurality of guides onto the spool, treated with adhesive and pulled, resulting in a bundle of polyamide polymer fibers.

The beam of polyamide polymer fibers obtained in this way was measured, determining its various physical properties, according to the procedures described below.

Fiber diameter

A cross section of a continuous thermoplastic polymer fiber was observed using a scanning electron microscope (SEM), and the fiber diameter was measured at 10 arbitrary points of the fiber to calculate the average value.

Linear density

The mass of one meter of fiber was measured, and the measured value was converted to linear density.

Tensile strength

A bundle of polyamide polymer fibers was subjected to tensile testing using an appropriate instrument at a temperature of 23 ° C and a relative humidity of 50%. The maximum voltage was divided by linear density in order to determine the strength per unit linear density.

The properties of a bundle of polyamide polymer fibers are summarized below in the table.

table 2 The number of polyamide polymer fiber Polyamide Fiber 1 Polyamide fiber 2 Polyamide Fiber 3 Type of polyamide polymer MPXD10 PXD10 MXD6 Linear density (dtex) 230 360 600 Tensile strength (gf / d) 6 3 four

2. Continuous carbon fiber

The continuous carbon fiber used here was as follows:

carbon fiber 1: TORAYCA T300-3000 polyacrylonitrile-based carbon fiber from Toray Industries, Inc., 3000 fibers per bundle, 1980 dtex linear density, 230 GPa tensile modulus, average diameter 7 μm.

3. The manufacture of fibrous web

Each fabric was woven using a rapier weaving machine and a bundle of polyamide polymer fibers as the main thread and a bundle of continuous carbon fibers as the weft thread obtained in the described manner. During this process, the number of threads was controlled so that the bundle of polyamide polymer fibers and the bundle of continuous carbon fibers, measured in an arbitrary square (X) of the fibrous web (here two opposite sides of the square (X) are oriented parallel to the main direction, and two the other sides are oriented parallel to the weft direction) had average values of fiber length (mm) and surface density, which are presented below in the table. Here, the average fiber length was measured by choosing an arbitrary square region of the fibrous web in which the two opposite sides are oriented parallel to the main direction, and the other two sides are oriented parallel to the weft direction, spreading the fiber bundle that makes up the fiber web, highlighting a single fiber and measuring its length using a ruler.

Bending Strength Measurement

The resulting fibrous webs were stacked and pressed when heated to a temperature that was 20 ° C higher than the melting point of the polyamide polymer and at a pressure of 3 MPa. A test specimen having dimensions of 2 mm (thickness) × 10 cm × 2 cm was cut from the obtained molded product and subjected to a study of bending strength according to JIS K7171.

Formability Measurement

Each fibrous web was pressed when heated in a hemispherical shape having a depth of 2 cm and a diameter of 2 cm, at a temperature that was 20 ° C higher than the melting point, and at a pressure of 1 MPa, to obtain a molded product. A molded product in which there were no deformations or wrinkles after molding was rated “good”, and a molded product in which deformations or wrinkles were observed was rated “unsatisfactory”.

Appearance of the molded product

The surfaces of the hemispherical samples described above and the surfaces of the hemispherical samples, which showed less disorder of the continuous carbon fiber, were rated “good”, and the surfaces of the hemispherical samples, which showed the disordering of the continuous carbon fiber and deterioration of appearance, were rated “unsatisfactory” "

The results are summarized in the table below.

Table 3 Example 1 Example 2 Example 3 Comparative Example 1 Reference Example 2 Type of Polyamide Polymer Fiber Polyamide Fiber 1 Polyamide fiber 2 Polyamide Fiber 3 Number 6 Polyamide Fiber 1
Continuous Carbon Fiber Type Carbon fiber 1 Carbon fiber 1 Carbon fiber 1 Carbon fiber 1 Carbon fiber 1 The average fiber length of the polyamide polymer fiber squared (X) (mm) eleven eleven 12 eleven 12 The average fiber length of the polyamide polymer fiber / side length of the square 1,1 1,1 1,2 1,1 1,2 The average length of the fiber continuous carbon fiber squared (X) (mm) fifteen fourteen 12 fourteen 17 Continuous carbon fiber average length / square side length 1,5 1.4 1,2 1.4 1.7 Surface density (g / m ² ) 370 350 400 350 400 Bending Strength (MPa) 800 900 1000 600 600 Suitability for forming a fibrous web OK OK OK OK OK Appearance of the molded product OK OK OK OK Unsatisfactory

As the table above clearly shows, it turned out that the fibrous webs according to the present invention have high mechanical strength and good formability. On the other hand, it was found that the fibrous web (comparative example 1) using polyamide polymer, which is not a polymer provided by the present invention, exhibits poor mechanical strength. Even if a polyamide polymer within the range provided by the present invention was used, it was found that the resulting molded product exhibits an unsatisfactory appearance when the average continuous carbon fiber length was outside the range of 1.1 times to 1.6 times the length of the side square (X) (comparative example 2).

Reference Example 3

The suitability for molding the composite material, which is described in Example 1 of Japanese Patent No. 4894982, was measured as described above. It was found that it has the same mechanical strength, but the carbon fiber on the surface turned out to be somewhat disordered, and the appearance of the molded product turned out to be worse than the floor compared to the molded product according to the present invention, although it remained at a practically suitable level.

Claims (13)

1. A fibrous web including main threads and weft threads, wherein yarns of one kind of warp and weft threads comprise a polyamide polymer fiber containing a polyamide polymer composition, and yarns of another type constitute a continuous carbon fiber; in an arbitrary square region of the fibrous web, one side of an arbitrary square region is oriented parallel to the warp threads, and the other side of an arbitrary square region is parallel to the weft threads, the continuous carbon fiber has an average length of 1.1-fold to 1.6- multiple lengths of the side of the square; the polyamide polymer composition comprises a polyamide polymer in which 50 mol% or more of diamine structural units forms xylylenediamine; and in which the polyamide polymer has a number average molecular weight (Mn) of from 6,000 to 30,000 and from 0.5 to 5% by weight of the polyamide polymer has a molecular weight of 1000 or less. 2. The fibrous web of claim 1, wherein the polyamide polymer fiber has an average length of 1.0 times to 1.6 times the length of the side of the square. 3. The fibrous web according to claim 1 or 2, having a surface density of from 50 to 1000 g / m ² . 4. The fibrous web according to claim 1 or 2, in which the polyamide polymer contains 0.01 to 1 wt.% Cyclic compounds. 5. The fibrous web according to claim 1 or 2, having a ratio of the average linear density of the polyamide polymer fiber and the average linear density of a continuous carbon fiber (average linear density of a polyamide polymer fiber / average linear density of a continuous carbon fiber) from 20/80 to 80/20. 6. The fibrous web according to claim 3, in which the polyamide polymer contains from 0.01 to 1 wt.% Cyclic compounds. 7. The fibrous web according to claim 3, having a ratio of the average linear density of the polyamide polymer fiber and the average linear density of a continuous carbon fiber (average linear density of a polyamide polymer fiber / average linear density of a continuous carbon fiber) from 20/80 to 80/20. 8. The fibrous web according to claim 4, having a ratio of the average linear density of the polyamide polymer fiber and the average linear density of a continuous carbon fiber (average linear density of a polyamide polymer fiber / average linear density of a continuous carbon fiber) from 20/80 to 80/20. 9. A molded product obtained by molding a fibrous web according to any one of paragraphs. 1-8.

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